Sulfite-free lamb burger meat: antimicrobial and antioxidant properties of green tea and carvacrol.

BACKGROUND: Sulfite is commonly used to preserve lamb burger meat in the EU. Nevertheless, its consumption has been related to certain health problems, which has increased consumer demand for sulfite-free products. Natural compounds with antioxidant and antimicrobial properties may be a feasible alternative to preserve lamb burger meat. This study evaluated the antimicrobial and antioxidant properties of carvacrol, green tea and their combination in preserving lamb burger meat. Their effect was also compared with that of 400 ppm sulfite. RESULTS: Lamb burger meat was mixed with different concentrations of the extracts, packaged aerobically and displayed for 8 days at 4 °C. Total polyphenols, thiobarbituric acid reactive substances, colour, and microbial and sensory analyses were performed. Both green tea and carvacrol avoided lipid oxidation even at 300 ppm, while only carvacrol, which showed a concentration-dependent action, delayed discolouration and microbial growth. Carvacrol and green tea also limited the development of oxidation odour and flavour, but the former brought about herbal odours and flavours to the meat. On the other hand, sulfite provided a higher colour stability and lower microbial counts than both natural compounds but presented a higher lipid oxidation. CONCLUSION: Carvacrol seems to be a promising alternative to replace sulfite in lamb burger meat, whereas green tea should be combined with an antimicrobial agent. © 2018 Society of Chemical Industry.

Supranutritional doses of vitamin E to improve lamb meat quality.

Vitamin E is a fat-soluble antioxidant, therefore, it can be stored in any fat depot in the body, where it exerts a potent chain-breaking antioxidant effect. Moreover, the antioxidant activity of vitamin E-like compounds is also present in meat post mortem. The deposition of tocopherol in the muscle depends on the dosage, the source, and the period of supplementation, so different dosage-time combinations have been developed. Vitamin E does not affect production parameters if minimum requirements for function and growth are satisfied, but it could influence lamb fatty acid profile. During display, it protects PUFA from degradation, reducing lipid oxidation and, therefore, delaying discolouration. Furthermore, vitamin E would indirectly affect the development of lamb aroma by reducing protein and lipid oxidation. To facilitate optimal supplementation rates by producers and retailers, the present paper reviews vitamin E chemistry, biochemistry, nutrition and its ability to maintain lamb quality.

Display stability of fresh and thawed lamb supplemented with vitamin E or sprayed with an antioxidant borage seed extract.

BACKGROUND: The commercialization of thawed lamb packaged in modified atmosphere and maintained on display could serve as an alternative capable of satisfying the requirements of both customers and distributors. However, previous studies have suggested that lipid oxidation may accelerate post-thawing because peroxidation occurs during frozen storage, thereby leading to rapid and severe secondary lipid oxidation. The addition of an antioxidant compound either in the lamb diet or in the packaged meat could resolve this problem. Therefore, the present study aimed to compare the effect of dietary vitamin E (1000 mg of dl-α-tocopheryl acetate per kg of basal diet) and the spraying of borage seed aqueous extract (10% p/v) on the quality of fresh and thawed lamb leg chops. RESULTS: Both borage extract and vitamin E improved colour (as measured via instrumental and visual assessment of colour) and lipid stability (thiobarbituric acid reactive substances) of fresh and thawed lamb throughout display, although neither of them had any antimicrobial effect. Freezing/thawing accelerated bone marrow darkening and reduced redness but delayed microbial growth. CONCLUSION: Both of these antioxidant strategies would be very profitable for the preservation of lamb meat, allowing thawed meat packaged in a modified atmosphere to be commercialized. However, additional studies should be carried out to determine how bone darkening in thawed chops can be avoided. © 2017 Society of Chemical Industry.